With the rapid development of electronics technology, electronic devices such as computers and mobile phones have become an indispensable part of life for modern people. The various parts of a computer, such as compact disc driver, graphics card, monitor, sound card and headset would consume large power in the course of standby, the problem of energy waste is caused. Therefore, how to reduce power consumption of the electronic devices is becoming an urgent topic to be solved.
In recent years, the power saving technology for electronic device has gradually developed. At present, most electronic devices generally adopt power saving modes to reduce the power consumption, and the electronic devices in the power saving modes will set a register provided by a microprocessor to be an idle mode, so that power consumption of circuits of the electronic devices can be reduced consequently. In order to meet the current trend of high environmental awareness and demands of related laws and regulations, especially when the power saving criterion of the electronic devices requires higher standard for power consumption, the microprocessor could not satisfy the criterion even if entering into the idle mode.